Dithiosemicarbazones



United States Patent 3,478,035 DI'I'HIOSEMICARBAZONES Paul Anthony Barrett, London, England, assignor to Burroughs Wellcome & Co. (U.S.A.) Inc., Tuckahoe, N.Y.,

a corporation of New York No Drawing. Filed July 21, 1965, Ser. No. 473,867 Claims priority, application Great Britain, July 23, 1964,

29,671/64; May 25, 1965, 22,006/65 Int. Cl. C0711 27/04; C07c 159/00; A61k 27/00 US. Cl. 260293.4 8 Claims ABSTRACT OF THE DISCLOSURE The invention is related to a-dith-iosemicarbazones having activity against coccidiosis and anaplasmosis. The compounds of the invention are of the formula where R is selected from the class consisting of hydrogen, lower alkoxy, lower alkyl, acetoxyrnethyl and phenyl, where R is selected from the class consisting of hydrogen, lower alkyl atoms, benzyl lower alkyl, cyclohexyl, benzyl and phenyl, A is selected from the class of a straight and branched chain alkylene having 1 to 8 carbon atoms and NR is selected from the class consisting of lower dialkylamino, pyrrolidino, piperidino and morpholino.

The present invention relates to a-dithiosemicarbazones having biological activity.

It has been found that the compounds of Formula I below and acid addition salts thereof are active against coccidiosis.

In Formula I, R is a hydrogen atom or an alkyl, cyclohexyl, benzyl, alkoxyalkyl, acetoxymethyl or phenyl group, R is a hydrogen atom or an alkyl, benzyl or phenyl group, A is divalent straight or branched alkylene group of 1 to 8 carbon atoms (preferably 2-5), and NR is a dialkylamino, pyrrolidino, piperidino or morpholino group. In general the activity is of a lower order when both R and R are hydrogen atoms though the two compounds glyoxal di-4-B-pyrrolidinoethylthiosemicarbazone (911062) and glyoxal di-[4-( -dibutylaminopropyl)thiosemicarbazone] (788C62) are exceptions to this rule. The acid which may be associated with the dithiosemicarbazone of Formula I is not critical for the biological activity and any acid may be used which is non-toxic and pharmaceutically acceptable, for example hydrochloric acid or oxalic acid.

The preferred compounds for activity against coccidiosis are:

acetylbenzoyl di-(448-diethylaminoethylthiosemicarbazone) (183C62),

diacetyl di-(4-,8-dimethylaminoethylthiosemicarbazone) acetylbenzoyl di-(4-,8-dimethylaminoethylthiosemicarbazone) (957C62),

diacetyl di-(4-B-morpholinoethylthiosemicarbazone) dipropionyl di-(4-{3-dimethylaminoethylthiosemicarbazone) (235064),

diacetyl di-(4-7-morpholinopropylthiacarbazone) diacetyl di-[4-(fl-piperidinoethyl)thiosemicarbazone] 1-phenylbutane-1,2-dione di-(4-p-dimethylaminoethylthiosemicarbazone) (41 1C64) ice octane-4,5-dione di-(4-,B-dimethylaminoethylthiosemicarbazone) (529064),

acetylbenzoyl di-(4 y-diethylaminopropylthiosemicarbazone) (236C64),

pentane-2,3-dione di-(4-B-dimethylaminoethylthiosemicarbazone) (294C6 1),

glyoxal di-[4-( -dibutylaminopropyl)thiosemicarbazone] (788C62), and

u-methoxyethylglyoxal di-(4-B-diethylaminoethylthiosemicarbazone) (956C62).

Thus the present invention provides the compounds of Formula I, and in particular the preferred compounds, named above.

The compounds of Formula I may be: made by reacting in acid solution two molecular proportions of a 4-substituted thiosemicarbazide of the formula with a glyoxal derivative of the formula R CO.CO.R wherein R R R and A have the above defined meanings, or one molecular proportion of the 4-substituted thiosernicarbazide with the corresponding ot-diketone mono-(4-substituted-thiosemicarbazonel. The reaction may be effected by heating the reactants together in a solvent wherein both of the reactants are soluble, and preferably at a slightly acidic pH. Thus ethanol or aqueous ethanol with an acid such as hydrochloride or acetic acid may be a suitable solvent. The resulting compounds are in general soluble substances in the form of their acid addition salts and the mixture may need to be made basic and cooled before the basic substance precipitates. The compounds can then be separated and purified by conventional techniques,

Thus in another aspect the present invention provides a method for preparing the compounds of Formula I substantially as described above.

Alternatively the compounds of Formula I may be synthesized by reacting 2 molecules of the appropriate dialkylaminoalkylamine with one molecule of the appropriate substituted glyoxal bis (methylcarbodithioylhydrazone) according to the reaction scheme.

This reaction may be carried out by heating the reactants together in a solvent.

Thus in another aspect the present invention provides this alternative method of synthesis of the compounds of Formula I.

As stated above the compounds of Formula I have activity against coccidiosis.

Coccidiosis is a disease of considerable economic importance in domestic animals throughout the world, particularly in all forms of poultry, and is caused by members of the genera Eimeria and lsospom of the taxonomic group coccidia.

The activity of the compounds was first detected by orally administering the compounds to chicks infected with Eimeria tenella: the compounds were effective in halting the development of the disease. The compounds were also found to be active against Eimeria acervulz'na, E. brunetti, E. maxima and E. necatrz'x in poultry both in preventing the disease developing in birds at risk and in halting the development of the disease in infected birds. They were also active against coccidia in other animals.

Thus in yet another aspect of the present invention provides a method of treating or preventing coccidiosis in domestic animals which comprises the oral administration of a compound of Formula I.

The compounds may be administered to the animals as a pharmaceutical formulation or as an additive to its food or drink, either alone or in combination with other coccidiostatic agents, with pharmaceutical carriers and excipients, or with other additives such as antibiotics and vitamins. Thus the compounds may be presented in the form of a standard pharmaceutical formulation or as an The compounds may be administered to the animal additive, as a concentrated food pre-mix containing the drug in a diluted form, or as a food containing the compound. The concentration should be such that the bird finally receives 0.001 to 0.1% by weight of the drug in its food for prophylactic use and a similar concentration in its drink for therapeutic use. It will be appreciated that if the compounds are used conjunction with other coccidiostatic agents the concentration may be lower.

Thus in still one further aspect the present invention provides a formulation for oral administration to animals which contains a compound of Formula I.

A further activity of compounds of Formula I is against anaplasmosis in cattle.

The disease, anaplasmosis, against which these cornpounds show activity, is a serious sytemic disease of cattle which is prevalent in large areas of the Asian, African, Australasian, and American continents and certain Southern areas of Europe which have a Mediterranean type of climate. The infecting anaplasm organism attacks the red blood cells of the cattle characteristically causing anaemia, general debility, and fever of the animal, which often prove fatal. The infecting anaplasm organism has not yet been fully characterised; it may be a protozoon but is believed more likely to be related to the rickettsiae. There are two species in cattle which are known as Aniaplasma marginale and Anapla'sma centrale the former being the more virulent. A milder form of anaplasmosis also affects sheep and goats in areas such as the Middle East, South Africa, and the United States of America.

According to the present invention in another aspect there is provided a method of treating animals suffering from anaplasmosis, which comprises the administration of a glyoxal dithiosemicarbazone of Formula I to the host.

As with the coccidiostatic activity, compounds wherein both R and R are hydrogen atoms have a lower order of activity than the other compounds of the general formula. The preferred compounds of Formula I for the treatment of anaplasmosis are diacetyl di-(4-B-dimethyl aminoethylthiosemicarbazone) (705C62), methoxymethylglyoxal di-(4 B diethylaminoethylthiosemicarbazone) (626062), and a-methoxyethylglyoxal di-(4-fl-diethylaminoethylthiosemicarbaz-one) (956C62).

The compounds may be presented either orally or parenterally, and the actual dose of the compound of Formula I required for treatment will vary somewhat according to the actual compound used, the method of administration and the size of the animal being treated. For cattle the doses will probably be in the range 5 mg./ kg. to 150 mg./kg., for example 2 doses of 30 mg./kg. given orally. When given parenterally the compounds are active at smaller doses.

The compounds of Formula I may be presented in a pharmaceutical formulation. For example, the oral formulations may be tablets, capsules, granules, powder, suspension, solutions, or emulsions which may contain diluents, binding agents, dispersing agents, surface-active agents, lubricating agents, coating materials, flavouring agents, colouring agents, solvents, thickening agents, suspending agents, or other pharmaceutically acceptable additives, and these formulations may be presented in unitdose form or multi-dose form or as additives to feed-stuffs.

The injectable form may be an aqueous or non-aqueous solution, suspension, or emulsion in a pharmaceutically acceptable liquid or mixture of liquids, which may contain bacteriostatic agents, antioxidants, buffers, solutes,

to render the solution isotonic with the blood, thickening agents, suspending agents, or other pharmaceutically acceptable additives. Such formulations are presented in unit forms such as ampoules or disposable injection devices, or in multi-dose forms such as a bottle from which the appropriate doses may be withdrawn. All such formulations should preferably be rendered sterile.

Thus in another aspect the invention provides pharmaceutical formulations containing a compound of Formula I.

The pharmaceutical formulations may be prepared by any of the standard methods of pharmacy and in yet one further aspect the present invention provides a method of making a pharmaceutical formulation containing a compound of Formula I which comprises the incorporation of the compound into the formulation by known techniques.

Yet another activity of the compounds of Formula I is against Aegyptianella pullorum in chicks. The followingcompounds were tested using 3 does of 10 mg./kg. given intramuscularly:

methylglyoxal di- [4- ,B-dimethylaminoethyl) thiosemicarbazone] (530C62), acetylbenzyl di{4-5-dimethylaminoethylthiosemicarbazone) (957C62), diacetyl di-(4-B-dimethylaminoethylthiosemicarbazone) (705C62), and acetylbenzoyl di-[4-(B-diethylaminoethyDthiose'micarbazone] (183C62).

The first two of these, 530C62 and 957C62, are the preferred compounds against Aegypti anella pullorum.

Still one further activity of the compounds of Formula I is against Babiesia rodhaini. Infected mice were subcutaneously injected with the compound using 25 mg./kg. The following compounds were tested and found active:

methoxymethylglyoxal di-(4-;8-dimethylaminoethylthiosemicarbazone) (528C64),

methylglyoxal di-[4-(fl-dimethylaminoethyl)thiosemicarbazone] (530C62),

acetylbenzoyl di-(4-{3-dimethylaminoethylthiosemicarbazone) (957C62),

diacetyl di- [4- 'y-dimethylaminopropyl thiosemicarbazone] (630C62), and

diacetyl di(4- 8-dimethylaminoethylthiosemicarbazone) The first two of these, 528C64 and 530C62 we're the most active against Babesia rodhalini.

The invention will now be particularly described with reference to the compounds of Formula I and formulations containing them.

When the abbreviations Ph, Me, Et, and Bu occur they denote phe'nyl, methyl, ethyl and n-butyl respectively. The symbols R R R and A have the same meanings as hereinbefore defined.

EXAMPLE 1 Acetophenone methyldithiocarbazate (112 g.) (prepared by the method of Kazakov and Postovakii, Doklady Akad, Nauk. S.S.S.R., 1960. 134, 824-abstracted in CA. 1961 55, 6483*) and diethylaminoethylamine (58 g.) in methanol (500 ml.) were boiled under reflux for 5 hours. The solvent was then removed by distillation in vacuo. The residual oil solidified and was recrystallised from light petroleum (B.P. 60-80 C.) to give aoetophenone 4-13- diethylaminoethyl-thiosemicarbazone (B.W. ref. No. 13.7C62), M.P. 82-83 C.

Acetophenone 4 B diethylaminoethyl thiosemicarbazone (43.8 g.) was dissolved in water (300' ml.) by the addition of concentrated hydrochloric acid (15 ml.). The mixture was then steam distilled until no further acetophenone distilled over. The residual aqueous solution of 4-B-diethylaminoethylthiosemicarbazide was cooled and acetylbenzoyl (11.1 g.) was added, together with sufficient ethanol to give a homogeneous solution when the mixture was heated to its boiling point. The mixture was boiled under reflux for half on hour, cooled, and basified by addition of saturated sodium carbon solution. The yellow oil which separated soon solidified and was filtered off, Washed with water, and recrystallised from 6 EXAMPLE 44 A hot solution of methyl dithiocarbazinate (42 g.) in ethanol (100 ml.) containing drops: of concentrated hydrochloric acid was prepared and to this a solution of diacetyl (14.8 g.) in ethanol (400 ml.) was added dropaqueous ethanol to give acetylbenzoyl di-(4-;3-diethyl- 5 wise with stirring over a period of minutes. Butaneaminoethylthiosemicarbazone) (B.W. ref. No. 183C62) 2,3-dione bis(methylcarbodithioyl hydr'azone) began to as yellow prisms, M.P.138-139. separate during the addition. The mixture was heated under reflux for a further 1 hour and then the hydrazone E MI )LES 2 53 10 was filtered off and washed with hot ethanol. It had a By the method as described in the first paragraph of mclting point of 220 C, with decomposition. Example 1 the followlng novel intermediates of the gen- A mixture of this butane-2,3-dione bis(methylcarbodieral formula Ph(CH )C:N.NH.CS.NHA---NR were thioylhydrazone) (4 g.) with ,B-dimethylaminoethylamine prepared. (4 g.) in ethanol ml.) was boiled under reflux for Melting point --A- NRZS Solvent for crystallisation in 0.

Intermediate Example:

i [CH' ]2 NMez Ethanol 108-110 Prryolidino do 125-127 Piperidinoo. 151 Morph olino .do 152 N M62 Light petroleum B.P. -100 C 96 NEtz Light petroleum Bl. 60-80 C--- 78 Pyrrolidino..- Ethanol 177-178 Morpholino.-- Light petroleum B.P. 6080 C B112 Ethyl acetate 1 85 N Eli: Light petroleum B.P. 60-80 C--- 60-61 Acid oxalate.

Using one of these intermediates and the appropriate glyoxal of formula R CO.CO.R the following dithiosemicarbazones were prepared according to the method described in the second paragraph of Example 1.

8 hours. After cooling, the mixture was filtered. The solid was dissolved in 0.5 N hydrochloric acid (50 ml.), some insoluble material was filtered off and discarded, the solution was made basic by addition of sodium carbonate solution, and the precipitated base was filtered off, dried, and re-crystallised from ethanol to give butane-2,3-dione di-(4-fl-dimethylaminoethylthiosemicarbazone) (B.W. ref.

DiHCl,

R! R A- NR Solvent for crystallisation lVLP., C. M.P., 0.

CH H CH2 z- NMez Aq. ethanol 158- CH3 CH3 CH1 NMe E h Ph CH3 CH3 H 0H3 OHa CHaOCI-Ia H GH OOH(GH3) H CHaCOOCH: H H H OH: H CH3 CH3 Ih CH3 0113 H CH CH3 CH3 H CH3 H CH3 CH3 CH3 H CH3 CH3 CHs H CH3 H H H CH3 H CH3 CH3 OH: H

s CH CH3 C3H] CHz]3 NElJz Acetate/petrol mixture...- 180 Ph CH3 [CH2]3-- NMe2 Benzene/petrol mixture- CH Morpholino. Cellosolve Ph d0 02115 Ph P11 Ph CH3 Ph Cyclohexyl CzHs Benzyl Benzyl Benzyl Benzyl Ph 1 Dioxalate.

7 No. 705C62) which had a melting point of 196 C. with decomposition: this was identical with the material described in Example 3.

EXAMPLE 45 According to the method of Example 44, butane-2,3- dione bis-(methyl-carbodithioyl hydrazone) and fl-morpholinoethylamine were reacted to give diacetyl di-4-flmorpholinoethylthiosemicarbazone (B.W. ref. N0. 207C64) M.P. 230 C. after crystallisation from Cellosolve: this was identical with the material described in Example 29.

EXAMPLE 46 Benzil bis-(methylcarbodithioyl hydrazone), M.P. 180-181 C. (decmp.) was prepared by a similar method to that described in the first part of Example 44, then 12 g. of this were reacted with fi-dimethylaminoethylamine (45 g.) in ethanol (45 ml.) by boiling under reflux for 1 hour. The ethanol and excess fi-dimethylarninoethylamine were distilled off under a water pump vacuum. The solid residue was boiled with ethanol and filtered off to give benzil bis-4-Q-dimethylaminoethylthiosemicarbazone (B.W. ref. No. 666C6 1) as pale yellow crystalls M.P. 22l223 C. (decomp.).

EXAMPLE 47 According to the method of Example 46 benzil bismethylcarbodithioyl hydrazone and p-diethylaminoethylamine were reacted together to give benzil bis-4-fi-diethylaminoethylthiosemicarbazone (B.W. ref. No. 869C64) M.P. 167 C. after recrystallisation from ethanol.

EXAMPLE 48 EXAMPLE 49 An oily injection suspension of diacetyl di-(4-[3-dimethylaminoethylthiosemicarbazone) (Examples 3 and 44) was prepared by incorporating the previously sterilised drug into previously sterilised arachis oil and ball milling the drug down to particle size of a or less. The concentration used was 100 mg. of drug per ml. of sus pension. The suspension was then put into the final container under aseptic conditions.

EXAMPLE 5 0 A wettable powder for making into drenches for cattle was made up as follows:

Component: Percent of weight Diacetyl di(4-;8-dimethylaminoethylthiosemicarbazone) 90 Cetrimide B.P. (surface active agent) 0.5 Sucrose 9.5

The drench can be prepared by weighing out the appropriate quantity of powder and adding this to water.

I claim:

1. A compound selected from the class consisting of acetylbenzoyl di-(4-,8-diethylaminoethylthiose'micarbazone),

diacetyl di-(4-,B-dimethylaminoethylthiosemicarbazone),

acetylbenzoyl di-(4-/8-dimety1aminoethylthiosemicarbazone),

diacetyl di-(4-,8-rnorpholinoethylthiosemicarbazone),

dipropionyl di-(4-,B-dimethylaminoethylthiosemicarbazone),

diacetyl di 4-'y-morpholinopropylthiosemicarbazone) diacetyl di-[4-(fl-piperidinoethyl)thiosemicarbazone],

.1-phenylbutane-1,2-dione di-(4-fl-dimethylaminoethylthiosemicarbazone),

octane-4,5-dione di-(4- 8-dimethylaminoethylthiosemicarbazone),

acetylbenzoyl di-(4-'y-diethylaminopropylthiosemicarbazone),

pentane-2,3-dione di-(4-j8-dimethylaminoethylthiosemicarbazone) glyoxal di- [4- ('y-dibutylaminopropyl thiosemicarbazone],

methoxymethylglyoxal di-(4-B-diethylaminoethylthiosemicarazones glyoxal di-(4-fl-pyrrolidinoethylthiosemicarbazone), and a-methoxyethylglyoxal di-(4-fl-diethylaminoethylthiosemicarbazone) 2. An addition salt of a compound of claim 1 with a pharmaceutically acceptable acid.

3. A compound selected from the class consisting of diacetyl di-(4-B-dimethylarninoethylthiosemicarbazone), methoxymethylglyoxal di- (4-13-diethylaminoethylthiosemicarbazone), and a-methoxy-ethylglyoxal di-(4-,B-diethylaminoethylthiosemicarbazone) 4. An addition salt of a compound of Formula 3 with a pharmaceutically acceptable acid.

5. A compound selected from the class consisting of glyoxal di-(4-B-pyrrolidinoethylthiosemicarbazone) and glyoxal di-[4-('y-dibutylaminopropyDthiosemicarbazone].

6. An addition salt of a compound of Formula 5 with a pharmaceutically acceptable acid.

7. Diacetyl di-[4-(,B-piperidinoethyl)thiosemicarbazone].

8. An addition salt of the compound of claim 7 with a pharmaceutically acceptable acid.

References Cited UNITED STATES PATENTS 2,657,234 10/1953 Klarcr et al. 260-552 FOREIGN PATENTS 1,298,323 6/1962 France.

OTHER REFERENCES French et al. (I), Cancer Research, vol. 18, No. 11 (1958), p. 1290.

French et al. (II), Cancer Research, vol. 20, No. 7 (1960), pp. 505-09, 518 and 519.

LEON ZITVER, Primary Examiner M. W. GLYNN, Assistant Examiner US. Cl. X.R. 

